The invention relates to a device for the lateral alignment of sheets in sheet deliverers of sheet-processing machines, particularly of printing machines.
Devices for the lateral alignment of sheets are intended to act upon distributed sheets and to ensure thereby the forming of a sheet stack of exact positioning and edge alignment and to fix in position the sheet stack thus formed.
Characteristics of known technological solutions German Pat. No. 494,007 discloses a device for the lateral alignment of stacking sheets. This device consists of fixed stops and of tappers linked to stops and spring-loaded, which will vertically oscillate against the stack and align the sheets on the stack.
The disadvantage of this device resides in the fact that the adjustment to the respective sheet width is difficult. When a sheet has a too large distance to the sheet stack the effect upon the sheet is too small, so that no exact stack can be formed. Too small distance to the stack will result in the tapper continuing to act upon the sheet when the sheet is already firmly resting on the stack. Damage to the sheet edges and to the printed image may thus be caused.
The greatest disadvantage of the tappers can be seen in the fact that their action upon the sheet is determined by the respective sheet edge. Sheets of differing cuts, and sheets that are shortened by the natural camber occurring during their falling phase, will not be influenced by the prior art joggers. Sheets of differing cuts will thus make impossible the forming of exact stacks.